summaryrefslogtreecommitdiff
path: root/server/providers/data_provider_be.c
blob: 55fc27877e3fb87788fd9cfab57b86e2d8941293 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
/*
   SSSD

   Data Provider Process

   Copyright (C) Simo Sorce <ssorce@redhat.com>	2008

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

#include <stdio.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <string.h>
#include <sys/time.h>
#include <errno.h>
#include <dlfcn.h>

#include <security/pam_appl.h>
#include <security/pam_modules.h>

#include "popt.h"
#include "util/util.h"
#include "confdb/confdb.h"
#include "db/sysdb.h"
#include "dbus/dbus.h"
#include "sbus/sssd_dbus.h"
#include "util/btreemap.h"
#include "providers/dp_backend.h"
#include "monitor/monitor_interfaces.h"

#define BE_CONF_ENTRY "config/domains/%s"

struct sbus_method monitor_be_methods[] = {
    { MON_CLI_METHOD_PING, monitor_common_pong },
    { MON_CLI_METHOD_RES_INIT, monitor_common_res_init },
    { NULL, NULL }
};

struct sbus_interface monitor_be_interface = {
    MONITOR_INTERFACE,
    MONITOR_PATH,
    SBUS_DEFAULT_VTABLE,
    monitor_be_methods,
    NULL
};

static int be_check_online(DBusMessage *message, struct sbus_connection *conn);
static int be_get_account_info(DBusMessage *message, struct sbus_connection *conn);
static int be_pam_handler(DBusMessage *message, struct sbus_connection *conn);

struct sbus_method be_methods[] = {
    { DP_CLI_METHOD_ONLINE, be_check_online },
    { DP_CLI_METHOD_GETACCTINFO, be_get_account_info },
    { DP_CLI_METHOD_PAMHANDLER, be_pam_handler },
    { NULL, NULL }
};

struct sbus_interface be_interface = {
    DP_CLI_INTERFACE,
    DP_CLI_PATH,
    SBUS_DEFAULT_VTABLE,
    be_methods,
    NULL
};

static struct bet_data bet_data[] = {
    {BET_NULL, NULL, NULL},
    {BET_ID, "provider", "sssm_%s_init"},
    {BET_AUTH, "auth-module", "sssm_%s_auth_init"},
    {BET_ACCESS, "access-module", "sssm_%s_access_init"},
    {BET_CHPASS, "chpass-module", "sssm_%s_chpass_init"},
    {BET_MAX, NULL, NULL}
};

struct be_async_req {
    be_req_fn_t fn;
    struct be_req *req;
};

static void be_async_req_handler(struct tevent_context *ev,
                                 struct tevent_timer *te,
                                 struct timeval tv, void *pvt)
{
    struct be_async_req *async_req;

    async_req = talloc_get_type(pvt, struct be_async_req);

    async_req->fn(async_req->req);
}

static int be_file_request(struct be_ctx *ctx,
                           be_req_fn_t fn,
                           struct be_req *req)
{
    struct be_async_req *areq;
    struct tevent_timer *te;
    struct timeval tv;

    if (!fn || !req) return EINVAL;

    areq = talloc(req, struct be_async_req);
    if (!areq) {
        return ENOMEM;
    }
    areq->fn = fn;
    areq->req = req;

    /* fire immediately */
    tv.tv_sec = 0;
    tv.tv_usec = 0;

    te = tevent_add_timer(ctx->ev, req, tv, be_async_req_handler, areq);
    if (te == NULL) {
        return EIO;
    }

    return EOK;
}

static void online_chk_callback(struct be_req *req, int status,
                                const char *errstr)
{
    struct be_online_req *oreq;
    DBusMessage *reply;
    DBusConnection *dbus_conn;
    dbus_bool_t dbret;
    dbus_uint16_t online;
    dbus_uint16_t err_maj = 0;
    dbus_uint32_t err_min = 0;
    const char *err_msg = "Success";

    oreq = talloc_get_type(req->req_data, struct be_online_req);

    if (status != EOK) {
        online = MOD_OFFLINE;
        err_maj = DP_ERR_FATAL;
        err_min = status;
        err_msg = errstr;
    }

    online = oreq->online;
    reply = (DBusMessage *)req->pvt;

    dbret = dbus_message_append_args(reply,
                                     DBUS_TYPE_UINT16, &online,
                                     DBUS_TYPE_UINT16, &err_maj,
                                     DBUS_TYPE_UINT32, &err_min,
                                     DBUS_TYPE_STRING, &err_msg,
                                     DBUS_TYPE_INVALID);
    if (!dbret) {
        DEBUG(1, ("Failed to generate dbus reply\n"));
        return;
    }

    dbus_conn = sbus_get_connection(req->be_ctx->dp_conn);
    dbus_connection_send(dbus_conn, reply, NULL);
    dbus_message_unref(reply);

    DEBUG(4, ("Request processed. Returned %d,%d,%s\n",
              err_maj, err_min, err_msg));

    /* finally free the request */
    talloc_free(req);
}


static int be_check_online(DBusMessage *message, struct sbus_connection *conn)
{
    struct be_online_req *req;
    struct be_req *be_req;
    struct be_ctx *ctx;
    DBusMessage *reply;
    dbus_bool_t dbret;
    void *user_data;
    int ret;
    dbus_uint16_t online;
    dbus_uint16_t err_maj;
    dbus_uint32_t err_min;
    const char *err_msg;

    user_data = sbus_conn_get_private_data(conn);
    if (!user_data) return EINVAL;
    ctx = talloc_get_type(user_data, struct be_ctx);
    if (!ctx) return EINVAL;

    reply = dbus_message_new_method_return(message);
    if (!reply) return ENOMEM;

    /* process request */
    be_req = talloc(ctx, struct be_req);
    if (!be_req) {
        online = MOD_OFFLINE;
        err_maj = DP_ERR_FATAL;
        err_min = ENOMEM;
        err_msg = "Out of memory";
        goto done;
    }
    be_req->be_ctx = ctx;
    be_req->fn = online_chk_callback;
    be_req->pvt = reply;

    req = talloc(be_req, struct be_online_req);
    if (!req) {
        online = MOD_OFFLINE;
        err_maj = DP_ERR_FATAL;
        err_min = ENOMEM;
        err_msg = "Out of memory";
        goto done;
    }
    req->online = 0;

    be_req->req_data = req;

    ret = be_file_request(ctx, ctx->bet_info[BET_ID].bet_ops->check_online, be_req);
    if (ret != EOK) {
        online = MOD_OFFLINE;
        err_maj = DP_ERR_FATAL;
        err_min = ret;
        err_msg = "Failed to file request";
        goto done;
    }

    return EOK;

done:
    if (be_req) {
        talloc_free(be_req);
    }

    dbret = dbus_message_append_args(reply,
                                     DBUS_TYPE_UINT16, &online,
                                     DBUS_TYPE_UINT16, &err_maj,
                                     DBUS_TYPE_UINT32, &err_min,
                                     DBUS_TYPE_STRING, &err_msg,
                                     DBUS_TYPE_INVALID);
    if (!dbret) return EIO;

    /* send reply back */
    sbus_conn_send_reply(conn, reply);
    dbus_message_unref(reply);

    return EOK;
}


static void acctinfo_callback(struct be_req *req, int status,
                              const char *errstr)
{
    DBusMessage *reply;
    DBusConnection *dbus_conn;
    dbus_bool_t dbret;
    dbus_uint16_t err_maj = 0;
    dbus_uint32_t err_min = 0;
    const char *err_msg = "Success";

    if (status != EOK) {
        err_maj = DP_ERR_FATAL;
        err_min = status;
        err_msg = errstr;
    }

    reply = (DBusMessage *)req->pvt;

    dbret = dbus_message_append_args(reply,
                                     DBUS_TYPE_UINT16, &err_maj,
                                     DBUS_TYPE_UINT32, &err_min,
                                     DBUS_TYPE_STRING, &err_msg,
                                     DBUS_TYPE_INVALID);
    if (!dbret) {
        DEBUG(1, ("Failed to generate dbus reply\n"));
        return;
    }

    dbus_conn = sbus_get_connection(req->be_ctx->dp_conn);
    dbus_connection_send(dbus_conn, reply, NULL);
    dbus_message_unref(reply);

    DEBUG(4, ("Request processed. Returned %d,%d,%s\n",
              err_maj, err_min, err_msg));

    /* finally free the request */
    talloc_free(req);
}

static int be_get_account_info(DBusMessage *message, struct sbus_connection *conn)
{
    struct be_acct_req *req;
    struct be_req *be_req;
    struct be_ctx *ctx;
    DBusMessage *reply;
    DBusError dbus_error;
    dbus_bool_t dbret;
    void *user_data;
    uint32_t type;
    char *attrs, *filter;
    int attr_type, filter_type;
    char *filter_val;
    int ret;
    dbus_uint16_t err_maj;
    dbus_uint32_t err_min;
    const char *err_msg;

    be_req = NULL;

    user_data = sbus_conn_get_private_data(conn);
    if (!user_data) return EINVAL;
    ctx = talloc_get_type(user_data, struct be_ctx);
    if (!ctx) return EINVAL;

    dbus_error_init(&dbus_error);

    ret = dbus_message_get_args(message, &dbus_error,
                                DBUS_TYPE_UINT32, &type,
                                DBUS_TYPE_STRING, &attrs,
                                DBUS_TYPE_STRING, &filter,
                                DBUS_TYPE_INVALID);
    if (!ret) {
        DEBUG(1,("Failed, to parse message!\n"));
        if (dbus_error_is_set(&dbus_error)) dbus_error_free(&dbus_error);
        return EIO;
    }

    DEBUG(4, ("Got request for [%u][%s][%s]\n", type, attrs, filter));

    reply = dbus_message_new_method_return(message);
    if (!reply) return ENOMEM;

    if (attrs) {
        if (strcmp(attrs, "core") == 0) attr_type = BE_ATTR_CORE;
        else if (strcmp(attrs, "membership") == 0) attr_type = BE_ATTR_MEM;
        else if (strcmp(attrs, "all") == 0) attr_type = BE_ATTR_ALL;
        else {
            err_maj = DP_ERR_FATAL;
            err_min = EINVAL;
            err_msg = "Invalid Attrs Parameter";
            goto done;
        }
    } else {
        err_maj = DP_ERR_FATAL;
        err_min = EINVAL;
        err_msg = "Missing Attrs Parameter";
        goto done;
    }

    if (filter) {
        if (strncmp(filter, "name=", 5) == 0) {
            filter_type = BE_FILTER_NAME;
            filter_val = &filter[5];
        } else if (strncmp(filter, "idnumber=", 9) == 0) {
            filter_type = BE_FILTER_IDNUM;
            filter_val = &filter[9];
        } else {
            err_maj = DP_ERR_FATAL;
            err_min = EINVAL;
            err_msg = "Invalid Filter";
            goto done;
        }
    } else {
        err_maj = DP_ERR_FATAL;
        err_min = EINVAL;
        err_msg = "Missing Filter Parameter";
        goto done;
    }

    /* process request */
    be_req = talloc(ctx, struct be_req);
    if (!be_req) {
        err_maj = DP_ERR_FATAL;
        err_min = ENOMEM;
        err_msg = "Out of memory";
        goto done;
    }
    be_req->be_ctx = ctx;
    be_req->fn = acctinfo_callback;
    be_req->pvt = reply;

    req = talloc(be_req, struct be_acct_req);
    if (!req) {
        err_maj = DP_ERR_FATAL;
        err_min = ENOMEM;
        err_msg = "Out of memory";
        goto done;
    }
    req->entry_type = type;
    req->attr_type = attr_type;
    req->filter_type = filter_type;
    req->filter_value = talloc_strdup(req, filter_val);

    be_req->req_data = req;

    ret = be_file_request(ctx, ctx->bet_info[BET_ID].bet_ops->handler, be_req);
    if (ret != EOK) {
        err_maj = DP_ERR_FATAL;
        err_min = ret;
        err_msg = "Failed to file request";
        goto done;
    }

    return EOK;

done:
    if (be_req) {
        talloc_free(be_req);
    }

    dbret = dbus_message_append_args(reply,
                                     DBUS_TYPE_UINT16, &err_maj,
                                     DBUS_TYPE_UINT32, &err_min,
                                     DBUS_TYPE_STRING, &err_msg,
                                     DBUS_TYPE_INVALID);
    if (!dbret) return EIO;

    DEBUG(4, ("Request processed. Returned %d,%d,%s\n",
              err_maj, err_min, err_msg));

    /* send reply back */
    sbus_conn_send_reply(conn, reply);
    dbus_message_unref(reply);

    return EOK;
}

static void be_pam_handler_callback(struct be_req *req, int status,
                                const char *errstr) {
    struct pam_data *pd;
    DBusMessage *reply;
    DBusConnection *dbus_conn;
    dbus_bool_t dbret;

    pd = talloc_get_type(req->req_data, struct pam_data);

    DEBUG(4, ("Sending result [%d][%s]\n", pd->pam_status, pd->domain));
    reply = (DBusMessage *)req->pvt;
    dbret = dp_pack_pam_response(reply, pd);
    if (!dbret) {
        DEBUG(1, ("Failed to generate dbus reply\n"));
        return;
    }

    dbus_conn = sbus_get_connection(req->be_ctx->dp_conn);
    dbus_connection_send(dbus_conn, reply, NULL);
    dbus_message_unref(reply);

    DEBUG(4, ("Sent result [%d][%s]\n", pd->pam_status, pd->domain));

    talloc_free(req);
}

static int be_pam_handler(DBusMessage *message, struct sbus_connection *conn)
{
    DBusError dbus_error;
    DBusMessage *reply;
    struct be_ctx *ctx;
    dbus_bool_t ret;
    void *user_data;
    struct pam_data *pd = NULL;
    struct be_req *be_req = NULL;
    uint32_t pam_status = PAM_SYSTEM_ERR;
    enum bet_type target = BET_NULL;

    user_data = sbus_conn_get_private_data(conn);
    if (!user_data) return EINVAL;
    ctx = talloc_get_type(user_data, struct be_ctx);
    if (!ctx) return EINVAL;

    reply = dbus_message_new_method_return(message);
    if (!reply) {
        DEBUG(1, ("dbus_message_new_method_return failed, cannot send reply.\n"));
        talloc_free(pd);
        return ENOMEM;
    }

    pd = talloc_zero(ctx, struct pam_data);
    if (!pd) return ENOMEM;

    dbus_error_init(&dbus_error);

    ret = dp_unpack_pam_request(message, pd, &dbus_error);
    if (!ret) {
        DEBUG(1,("Failed, to parse message!\n"));
        talloc_free(pd);
        return EIO;
    }

    DEBUG(4, ("Got request with the following data\n"));
    DEBUG_PAM_DATA(4, pd);

    switch (pd->cmd) {
        case SSS_PAM_AUTHENTICATE:
            target = BET_AUTH;
            break;
        case SSS_PAM_ACCT_MGMT:
            target = BET_ACCESS;
            break;
        case SSS_PAM_CHAUTHTOK:
            target = BET_CHPASS;
            break;
        default:
            DEBUG(7, ("Unsupported PAM command [%d].\n", pd->cmd));
            pam_status = PAM_SUCCESS;
            ret = EOK;
            goto done;
    }

    /* return an error if corresponding backend target is configured */
    if (!ctx->bet_info[target].bet_ops) {
        DEBUG(7, ("Undefined backend target.\n"));
        goto done;
    }

    be_req = talloc_zero(ctx, struct be_req);
    if (!be_req) {
        DEBUG(7, ("talloc_zero failed.\n"));
        goto done;
    }

    be_req->be_ctx = ctx;
    be_req->fn = be_pam_handler_callback;
    be_req->pvt = reply;
    be_req->req_data = pd;

    ret = be_file_request(ctx, ctx->bet_info[target].bet_ops->handler, be_req);
    if (ret != EOK) {
        DEBUG(7, ("be_file_request failed.\n"));
        goto done;
    }

    return EOK;

done:
    talloc_free(be_req);

    DEBUG(4, ("Sending result [%d][%s]\n", pam_status, ctx->domain->name));
    ret = dbus_message_append_args(reply,
                                   DBUS_TYPE_UINT32, &pam_status,
                                   DBUS_TYPE_STRING, &ctx->domain->name,
                                   DBUS_TYPE_INVALID);
    if (!ret) return EIO;

    /* send reply back immediately */
    sbus_conn_send_reply(conn, reply);
    dbus_message_unref(reply);

    talloc_free(pd);
    return EOK;
}

/* mon_cli_init
 * sbus channel to the monitor daemon */
static int mon_cli_init(struct be_ctx *ctx)
{
    char *sbus_address;
    int ret;

    /* Set up SBUS connection to the monitor */
    ret = monitor_get_sbus_address(ctx, ctx->cdb, &sbus_address);
    if (ret != EOK) {
        DEBUG(0, ("Could not locate monitor address.\n"));
        return ret;
    }

    ret = sbus_client_init(ctx, ctx->ev, sbus_address,
                           &monitor_be_interface, &ctx->mon_conn,
                           NULL, ctx);
    if (ret != EOK) {
        DEBUG(0, ("Failed to connect to monitor services.\n"));
        return ret;
    }

    /* Identify ourselves to the monitor */
    ret = monitor_common_send_id(ctx->mon_conn,
                                 ctx->identity,
                                 DATA_PROVIDER_VERSION);
    if (ret != EOK) {
        DEBUG(0, ("Failed to identify to the monitor!\n"));
        return ret;
    }

    return EOK;
}

static void be_cli_reconnect_init(struct sbus_connection *conn, int status, void *pvt);

/* be_cli_init
 * sbus channel to the data provider daemon */
static int be_cli_init(struct be_ctx *ctx)
{
    int ret, max_retries;
    char *sbus_address;

    /* Set up SBUS connection to the monitor */
    ret = dp_get_sbus_address(ctx, ctx->cdb, &sbus_address);
    if (ret != EOK) {
        DEBUG(0, ("Could not locate monitor address.\n"));
        return ret;
    }

    ret = sbus_client_init(ctx, ctx->ev, sbus_address,
                           &be_interface, &ctx->dp_conn,
                           NULL, ctx);
    if (ret != EOK) {
        DEBUG(0, ("Failed to connect to monitor services.\n"));
        return ret;
    }

    /* Identify ourselves to the data provider */
    ret = dp_common_send_id(ctx->dp_conn,
                            DP_CLI_BACKEND, DATA_PROVIDER_VERSION,
                            "", ctx->domain->name);
    if (ret != EOK) {
        DEBUG(0, ("Failed to identify to the data provider!\n"));
        return ret;
    }

    /* Enable automatic reconnection to the Data Provider */
    ret = confdb_get_int(ctx->cdb, ctx, SERVICE_CONF_ENTRY,
                         "reconnection_retries", 3, &max_retries);
    if (ret != EOK) {
        DEBUG(0, ("Failed to set up automatic reconnection\n"));
        return ret;
    }

    sbus_reconnect_init(ctx->dp_conn, max_retries,
                        be_cli_reconnect_init, ctx);

    return EOK;
}

static int be_finalize(struct be_ctx *ctx);
static void be_shutdown(struct be_req *req, int status, const char *errstr);

static void be_cli_reconnect_init(struct sbus_connection *conn, int status, void *pvt)
{
    int ret;
    struct be_ctx *be_ctx = talloc_get_type(pvt, struct be_ctx);

    /* Did we reconnect successfully? */
    if (status == SBUS_RECONNECT_SUCCESS) {
        DEBUG(1, ("Reconnected to the Data Provider.\n"));

        /* Identify ourselves to the data provider */
        ret = dp_common_send_id(be_ctx->dp_conn,
                                DP_CLI_BACKEND, DATA_PROVIDER_VERSION,
                                "", be_ctx->domain->name);
        if (ret != EOK) {
            DEBUG(0, ("Failed to send id to the data provider!\n"));
        } else {
            return;
        }
    }

    /* Handle failure */
    DEBUG(0, ("Could not reconnect to data provider.\n"));

    /* Kill the backend and let the monitor restart it */
    ret = be_finalize(be_ctx);
    if (ret != EOK) {
        DEBUG(0, ("Finalizing back-end failed with error [%d] [%s]\n",
                  ret, strerror(ret)));
        be_shutdown(NULL, ret, NULL);
    }
}

static void be_shutdown(struct be_req *req, int status, const char *errstr)
{
    /* Nothing left to do but exit() */
    if (status == EOK)
        exit(0);

    /* Something went wrong in finalize */
    DEBUG(0, ("Finalizing auth module failed with error [%d] [%s]\n",
              status, errstr ? : strerror(status)));

    exit(1);
}

static void be_id_shutdown(struct be_req *req, int status, const char *errstr)
{
    struct be_req *shutdown_req;
    struct be_ctx *ctx;
    int ret;

    if (status != EOK) {
        /* Something went wrong in finalize */
        DEBUG(0, ("Finalizing auth module failed with error [%d] [%s]\n",
                  status, errstr ? : strerror(status)));
    }

    ctx = req->be_ctx;

    /* Now shutdown the id module too */
    shutdown_req = talloc_zero(ctx, struct be_req);
    if (!shutdown_req) {
        ret = ENOMEM;
        goto fail;
    }

    shutdown_req->be_ctx = ctx;
    shutdown_req->fn = be_id_shutdown;

    shutdown_req->pvt = ctx->bet_info[BET_ID].pvt_bet_data;

    ret = be_file_request(ctx, ctx->bet_info[BET_ID].bet_ops->finalize, shutdown_req);
    if (ret == EOK)
        return;

fail:
    /* If we got here, we couldn't shut down cleanly. */
    be_shutdown(NULL, ret, NULL);
}

static int be_finalize(struct be_ctx *ctx)
{
    struct be_req *shutdown_req;
    int ret;

    shutdown_req = talloc_zero(ctx, struct be_req);
    if (!shutdown_req) {
        ret = ENOMEM;
        goto fail;
    }

    shutdown_req->be_ctx = ctx;
    shutdown_req->fn = be_id_shutdown;
    shutdown_req->pvt = ctx->bet_info[BET_AUTH].pvt_bet_data;

    ret = be_file_request(ctx, ctx->bet_info[BET_AUTH].bet_ops->finalize, shutdown_req);
    if (ret == EOK) return EOK;

fail:
    /* If we got here, we couldn't shut down cleanly. */
    DEBUG(0, ("ERROR: could not shut down cleanly.\n"));
    return ret;
}

static void be_target_access_permit(struct be_req *be_req)
{
    struct pam_data *pd = talloc_get_type(be_req->req_data, struct pam_data);
    DEBUG(9, ("be_target_access_permit called, returning PAM_SUCCESS.\n"));

    pd->pam_status = PAM_SUCCESS;
    be_req->fn(be_req, PAM_SUCCESS, NULL);
}

static struct bet_ops be_target_access_permit_ops = {
    .check_online = NULL,
    .handler = be_target_access_permit,
    .finalize = NULL
};

static int load_backend_module(struct be_ctx *ctx,
                               enum bet_type bet_type,
                               struct bet_ops **be_ops,
                               void **be_pvt_data)
{
    TALLOC_CTX *tmp_ctx;
    int ret = EINVAL;
    bool already_loaded = false;
    int lb=0;
    char *mod_name = NULL;
    char *path = NULL;
    void *handle;
    char *mod_init_fn_name = NULL;
    bet_init_fn_t mod_init_fn = NULL;

    if (bet_type <= BET_NULL || bet_type >= BET_MAX ||
        bet_type != bet_data[bet_type].bet_type) {
        DEBUG(2, ("invalid bet_type or bet_data corrupted.\n"));
        return EINVAL;
    }

    tmp_ctx = talloc_new(ctx);
    if (!tmp_ctx) {
        DEBUG(7, ("talloc_new failed.\n"));
        return ENOMEM;
    }

    ret = confdb_get_string(ctx->cdb, tmp_ctx, ctx->conf_path,
                            bet_data[bet_type].option_name, NULL,
                            &mod_name);
    if (ret != EOK) {
        ret = EFAULT;
        goto done;
    }
    if (!mod_name) {
        ret = ENOENT;
        goto done;
    }

    mod_init_fn_name = talloc_asprintf(tmp_ctx,
                                       bet_data[bet_type].mod_init_fn_name_fmt,
                                       mod_name);
    if (mod_init_fn_name == NULL) {
        DEBUG(7, ("talloc_asprintf failed\n"));
        ret = ENOMEM;
        goto done;
    }


    lb = 0;
    while(ctx->loaded_be[lb].be_name != NULL) {
        if (strncmp(ctx->loaded_be[lb].be_name, mod_name,
                    strlen(mod_name)) == 0) {
            DEBUG(7, ("Backend [%s] already loaded.\n", mod_name));
            already_loaded = true;
            break;
        }

        ++lb;
        if (lb >= BET_MAX) {
            DEBUG(2, ("Backend context corrupted.\n"));
            return EINVAL;
        }
    }

    if (!already_loaded) {
        path = talloc_asprintf(tmp_ctx, "%s/libsss_%s.so",
                               DATA_PROVIDER_PLUGINS_PATH, mod_name);
        if (!path) {
            return ENOMEM;
        }

        DEBUG(7, ("Loading backend [%s] with path [%s].\n", mod_name, path));
        handle = dlopen(path, RTLD_NOW);
        if (!handle) {
            DEBUG(0, ("Unable to load %s module with path (%s), error: %s\n",
                      mod_name, path, dlerror()));
            ret = ELIBACC;
            goto done;
        }

        ctx->loaded_be[lb].be_name = talloc_strdup(ctx, mod_name);
        ctx->loaded_be[lb].handle = handle;
    }

    mod_init_fn = (bet_init_fn_t)dlsym(ctx->loaded_be[lb].handle,
                                           mod_init_fn_name);
    if (mod_init_fn == NULL) {
        DEBUG(0, ("Unable to load init fn %s from module %s, error: %s\n",
                  mod_init_fn_name, mod_name, dlerror()));
        ret = ELIBBAD;
        goto done;
    }

    ret = mod_init_fn(ctx, be_ops, be_pvt_data);
    if (ret != EOK) {
        DEBUG(0, ("Error (%d) in module (%s) initialization (%s)!\n",
                  ret, mod_name, mod_init_fn_name));
        goto done;
    }

    ret = EOK;

done:
    talloc_free(tmp_ctx);
    return ret;
}

/* Some providers are just aliases for more complicated settings,
 * rewrite the alias into the actual settings */
static int be_rewrite(struct be_ctx *ctx)
{
    int ret;
    const char *val[2];
    val[1] = NULL;
    char **get_values = NULL;

    /* "files" is a special case that means:
     *  provider = proxy
     *  libName  = files
     */
    ret = confdb_get_param(ctx->cdb, ctx, ctx->conf_path, "provider",
                           &get_values);
    if (ret != EOK) {
        DEBUG(1, ("Failed to read provider from confdb.\n"));
        return ret;
    }
    if (get_values[0] == NULL) {
        DEBUG(1, ("Missing provider.\n"));
        return EINVAL;
    }

    if (strcasecmp(get_values[0], "files") == 0) {
        DEBUG(5, ("Rewriting provider %s\n", get_values[0]));
        talloc_zfree(get_values);

        val[0] = "proxy";
        ret = confdb_add_param(ctx->cdb, true,
                               ctx->conf_path,
                               "provider",
                               val);
        if (ret) {
            return ret;
        }

        val[0] = "files";
        ret = confdb_add_param(ctx->cdb, true,
                               ctx->conf_path,
                               "libName",
                               val);
        if (ret) {
            return ret;
        }
    }

    return EOK;
}

int be_process_init(TALLOC_CTX *mem_ctx,
                    const char *be_domain,
                    struct tevent_context *ev,
                    struct confdb_ctx *cdb)
{
    struct be_ctx *ctx;
    int ret;

    ctx = talloc_zero(mem_ctx, struct be_ctx);
    if (!ctx) {
        DEBUG(0, ("fatal error initializing be_ctx\n"));
        return ENOMEM;
    }
    ctx->ev = ev;
    ctx->cdb = cdb;
    ctx->identity = talloc_asprintf(ctx, "%%BE_%s", be_domain);
    ctx->conf_path = talloc_asprintf(ctx, "config/domains/%s", be_domain);
    if (!ctx->identity || !ctx->conf_path) {
        DEBUG(0, ("Out of memory!?\n"));
        return ENOMEM;
    }

    ret = confdb_get_domain(cdb, be_domain, &ctx->domain);
    if (ret != EOK) {
        DEBUG(0, ("fatal error retrieving domain configuration\n"));
        return ret;
    }

    ret = sysdb_domain_init(ctx, ev, ctx->domain, DB_PATH, &ctx->sysdb);
    if (ret != EOK) {
        DEBUG(0, ("fatal error opening cache database\n"));
        return ret;
    }

    ret = mon_cli_init(ctx);
    if (ret != EOK) {
        DEBUG(0, ("fatal error setting up monitor bus\n"));
        return ret;
    }

    ret = be_cli_init(ctx);
    if (ret != EOK) {
        DEBUG(0, ("fatal error setting up server bus\n"));
        return ret;
    }

    ret = be_rewrite(ctx);
    if (ret != EOK) {
        DEBUG(0, ("error rewriting provider types\n"));
        return ret;
    }

    ret = load_backend_module(ctx, BET_ID,
                              &ctx->bet_info[BET_ID].bet_ops,
                              &ctx->bet_info[BET_ID].pvt_bet_data);
    if (ret != EOK) {
        DEBUG(0, ("fatal error initializing data providers\n"));
        return ret;
    }

    ret = load_backend_module(ctx, BET_AUTH,
                              &ctx->bet_info[BET_AUTH].bet_ops,
                              &ctx->bet_info[BET_AUTH].pvt_bet_data);
    if (ret != EOK) {
        if (ret != ENOENT) {
            DEBUG(0, ("fatal error initializing data providers\n"));
            return ret;
        }
        DEBUG(1, ("No authentication module provided for [%s] !!\n",
                  be_domain));
    }

    ret = load_backend_module(ctx, BET_ACCESS,
                              &ctx->bet_info[BET_ACCESS].bet_ops,
                              &ctx->bet_info[BET_ACCESS].pvt_bet_data);
    if (ret != EOK) {
        if (ret != ENOENT) {
            DEBUG(0, ("fatal error initializing data providers\n"));
            return ret;
        }
        DEBUG(1, ("No access control module provided for [%s] "
                  "using be_target_access_permit!!\n", be_domain));
        ctx->bet_info[BET_ACCESS].bet_ops = &be_target_access_permit_ops;
        ctx->bet_info[BET_ACCESS].pvt_bet_data = NULL;
    }

    ret = load_backend_module(ctx, BET_CHPASS,
                              &ctx->bet_info[BET_CHPASS].bet_ops,
                              &ctx->bet_info[BET_CHPASS].pvt_bet_data);
    if (ret != EOK) {
        if (ret != ENOENT) {
            DEBUG(0, ("fatal error initializing data providers\n"));
            return ret;
        }
        DEBUG(1, ("No change password module provided for [%s] !!\n",
                  be_domain));
    }

    return EOK;
}

int main(int argc, const char *argv[])
{
    int opt;
    poptContext pc;
    char *be_domain = NULL;
    char *srv_name = NULL;
    char *conf_entry = NULL;
    struct main_context *main_ctx;
    int ret;

    struct poptOption long_options[] = {
        POPT_AUTOHELP
        SSSD_MAIN_OPTS
        {"domain", 0, POPT_ARG_STRING, &be_domain, 0,
         "Domain of the information provider (mandatory)", NULL },
        POPT_TABLEEND
    };

    pc = poptGetContext(argv[0], argc, argv, long_options, 0);
    while((opt = poptGetNextOpt(pc)) != -1) {
        switch(opt) {
        default:
        fprintf(stderr, "\nInvalid option %s: %s\n\n",
                  poptBadOption(pc, 0), poptStrerror(opt));
            poptPrintUsage(pc, stderr, 0);
            return 1;
        }
    }

    if (be_domain == NULL) {
        fprintf(stderr, "\nMissing option, --domain is a mandatory option.\n\n");
            poptPrintUsage(pc, stderr, 0);
            return 1;
    }

    poptFreeContext(pc);

    /* set up things like debug , signals, daemonization, etc... */
    srv_name = talloc_asprintf(NULL, "sssd[be[%s]]", be_domain);
    if (!srv_name) return 2;

    conf_entry = talloc_asprintf(NULL, BE_CONF_ENTRY, be_domain);
    if (!conf_entry) return 2;

    ret = server_setup(srv_name, 0, conf_entry, &main_ctx);
    if (ret != EOK) {
        DEBUG(0, ("Could not set up mainloop [%d]\n", ret));
        return 2;
    }

    ret = die_if_parent_died();
    if (ret != EOK) {
        /* This is not fatal, don't return */
        DEBUG(2, ("Could not set up to exit when parent process does\n"));
    }

    ret = be_process_init(main_ctx,
                          be_domain,
                          main_ctx->event_ctx,
                          main_ctx->confdb_ctx);
    if (ret != EOK) {
        DEBUG(0, ("Could not initialize backend [%d]\n", ret));
        return 3;
    }

    DEBUG(1, ("Backend provider (%s) started!\n", be_domain));

    /* loop on main */
    server_loop(main_ctx);

    return 0;
}